The Nagasaki terror weapon (3)
I believe the answer is:
gas
'the' is the definition.
I can't judge whether this defines the answer.
'nagasaki terror weapon' is the wordplay.
'GAS' is hidden within the letters.
However, I'm not sure how this is indicated.
Can you help me to learn more?
(Other definitions for gas that I've seen before include "person who's amusing ..." , "Hydrogen or methane, say" , "Oxygen is one" , "Something exciting" , "It's not liquid or solid, like American petrol" .)